Journal List > Korean J Phys Anthropol > v.26(1) > 1039140

Kim and Cho: Difference of Second to Fourth Digit Ratio according to the Methods of Measuring Length


The 2nd to 4th digit ratio (2D : 4D) reflects exposure level of sex hormones in fetal period and there are various methods for finger length measurement. The aim of this study is to identify an accurate and effective method for finger length measurement.
This study was done on 272 individuals (115 males, 157 females). Data were collected by measuring index and ring finger length on both hands by calipers, ruler, photocopy, and radiography. The data were analyzed through independent t-test, paired t-test, Pearson correlation analysis using SPSS win 19.0.
This study showed that the 2nd and 4th finger measured by radiography were the longest finger both of males and females and revealed the largest length difference between 2nd and 4th finger. There were significant sex differences all of 4 measurement methods in 2D : 4D, especially remarkable sex difference by radiography and photography. The 2D : 4D by indirect measurement was lower than that of direct measurement. Correlation between digit ratio by radiography and by photocopy was 0.590 and correlation between digit ratio by radiography and by calipers was 0.586.
The results of this study suggest that indirect measurement by radiography can be alternated by photocopy primarily and by calipers secondarily.

Figures and Tables

Fig. 1
Second and fourth finger length by radiography was measured from proximl end of proximal phalanx to distal end of distal phalanx.
Table 1
Differences of second and fourth finger length according to measurement method (N=272)

2D : 4D; second to fourth digit ratio

M; mean, SD; standard deviation

Table 2
Sex differences of second to fourth digit ratio according to measurement method (N=272)

2D : 4D; second to fourth digit ratio

M; mean, SD; standard deviation

*p<0.05, **p<0.01, ***p<0.001

Table 3
Differences of measurement method in second to fourth digit ratio (N=272)

2D : 4D; second to fourth digit ratio

M; mean, SD: standard deviation

*; Significant difference (p<0.001) between measurement methods in males

; Significant difference (p<0.001) between measurement methods in females

Table 4
Correlation among digit ratios according to measurement method of finger length (N=272)

2D : 4D; second to fourth digit ratio

By Pearson's correlation analysis, *p<0.001


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